This invention relates to a plate-type filter press having a cleaning truck transportable in the direction of movement of the slidable filter plates and embodying a drive and a pusher adapted to be brought into engagement with the filter plates.
As is well known, in plate-type filter presses, filter cake accumulates between adjacent plates in the filter chamber and is discharged after the plates are opened. However, the filter cloths covering the filter plates become clogged during the course of use, so that their permeability is greatly decreased and the filter capacity is considerably reduced. It is therefore necessary to clean the cloths after they have been in use for fairly long intervals of time.
To clean the filter cloths, it is customary to use spray pipes having nozzles directed towards the filter surface. Such spray pipes are supplied with water under pressure, and depending upon the arrangement, are moved either horizontally or vertically along the surface to be cleaned. The guide means and drive means for the spray pipes are located on the cleaning truck. There are various types of such filter cloth cleaning devices which are well known in the art. If only one interstice between two plates is available at a time, then the two surfaces will be cleaned with two oppositely directed rows of nozzles. If each plate is accessible from both sides, then two spray pipes may be used to clean off both sides of the plates simultaneously.
Prior art apparatus of the above type is disclosed in Offenlegungsschrift No. 28 22 202 wherein the cleaning truck must move relative to the filter plates in order to slide the filter plates consecutively against the open pressure pad or the filter plates already present at this location. The cleaning truck then returns to its cleaning position above the next filter plate. Accordingly, the cleaning truck requires a reversible drive and the control means for bringing about such oscillating, travelling movements is also complicated.